This part is no longer available from Yamaha. It has been discontinued. This part is a new reproduction of the original. The originals have deteriorated with time, as they are 52+ years old. The part number is used for reference purposes only and no source of manufacture or supply is implied. These are a great replacement at a fair price. The chrome is comparable to the original. 
 
(concourse correct for 1968-1970 models. 1971-1973 went to a slightly different looking bracket).
 
This part will fit the following models:
1968 Yamaha DT1
1969 Yamaha AT1M
1969 Yamaha CT1
1969 Yamaha DT1B
1969 Yamaha DT1S
1970 Yamaha AT1BM
1970 Yamaha CT1B
1970 Yamaha DT1C
1970 Yamaha RT1
1971 Yamaha CT1C
1971 Yamaha DT1E
1971 Yamaha RT1B
1972 Yamaha CT2
1972 Yamaha DT2
1972 Yamaha RT2
1973 Yamaha CT3
 
These will not fit the AT1/AT2/AT3 Enduros (those versions are different)
Also it will not fit the 1973 DT3 or RT3 without modification.